package main

import "fmt"

var (
    allStudent map[int64]*student
)

type student struct {
    id   int64
    name string
}

func newStudent(id int64, name string) *student {
    return &student{
        id:   id,
        name: name,
    }
}

func showAllStudent() {
    for k, v := range allStudent {
        fmt.Printf("学号:%d  姓名:%s\n", k, v.name)
    }
}

func addStudent() {
    var id int64
    var name string
    fmt.Println("输入ID:")
    fmt.Scanln(&id)
    fmt.Println("输入学生名：")
    fmt.Scanln(&name)
    stu := newStudent(id, name)
    allStudent[id] = stu
}

func removeStudent() {
    var id int64
    fmt.Println("输入ID:")
    fmt.Scanln(&id)
    fmt.Println("删除:", allStudent[id])
    delete(allStudent, id)
}

func main() {
    allStudent = make(map[int64]*student)
    for {

        fmt.Println(`
    1.查看所有学生
    2.添加学生
    3.删除学生
    4.退出
    `)
        var ch int8
        fmt.Print("\n\n请选择：")
        fmt.Scanln(&ch)
        fmt.Printf("您选择了:%d\n", ch)
        switch ch {
        case 1:
            showAllStudent()
        case 2:
            addStudent()
        case 3:
            removeStudent()
        case 4:
            return
        default:
            continue
        }
    }
}